{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T05:13:06Z","timestamp":1789103586699,"version":"build-2803163510"},"reference-count":64,"publisher":"BMJ","issue":"4","license":[{"start":{"date-parts":[[2021,4,26]],"date-time":"2021-04-26T00:00:00Z","timestamp":1619395200000},"content-version":"unspecified","delay-in-days":25,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/100008548","name":"Harvard T.H. Chan School of Public Health","doi-asserted-by":"publisher","award":["5105921_263681"],"award-info":[{"award-number":["5105921_263681"]}],"id":[{"id":"10.13039\/100008548","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Funding for this study received by a grant from an anonymous donor to Harvard T.H. Chan School of Public Health"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2021,2,25]]},"published-print":{"date-parts":[[2021,4]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Birth spacing is a critical pathway to improving reproductive health. WHO recommends a minimum of 33-month interval between two consecutive births to reduce maternal, perinatal, infant morbidity and mortality. Our study evaluated factors associated with short birth intervals (SBIs) of less than 33 months between two consecutive births, in Karachi, Pakistan.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We used data from a cross-sectional study among married women of reproductive age (MWRA) who had at least one live birth in the 6\u2009years preceding the survey (N=2394). Information regarding their sociodemographic characteristics, reproductive history, fertility preferences, family planning history and a 6-year reproductive calendar were collected. To identify factors associated with SBIs, we fitted simple and multiple Cox proportional hazards models and computed HRs with their 95% CIs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The median birth interval was 25 months (IQR: 14\u201339 months), with 22.9% (833) of births occurring within 33 months of the index birth. Women\u2019s increasing age (25\u201330 years (aHR 0.63 (0.53 to 0.75), 30+ years (aHR 0.29, 95%\u2009CI 0.22 to 0.39) compared with 20-24 years; secondary education (aHR 0.75, 95%\u2009CI 0.63 to 0.88), intermediate education (aHR 0.62, 95%\u2009CI 0.48 to 0.80), higher education (aHR 0.69, 95%\u2009CI 0.51 to 0.92) compared with no education, and a male child of the index birth (aHR 0.81, 95%\u2009CI 0.70 to 0.94) reduced the likelihood of SBIs. Women\u2019s younger age &lt;20 years (aHR 1.24, 95%\u2009CI 1.05 to 1.24) compared with 20\u201324 years, and those who did not use contraception within 9\u2009months of the index birth had a higher likelihood for SBIs for succeeding birth compared with those who used contraception (aHR 2.23, 95%\u2009CI 1.93 to 2.58).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Study shows that birth intervals in the study population are lower than the national average. To optimise birth intervals, programmes should target child spacing strategies and counsel MWRA on the benefits of optimal birth spacing, family planning services and contraceptive utilisation.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2020-043786","type":"journal-article","created":{"date-parts":[[2021,4,26]],"date-time":"2021-04-26T11:30:43Z","timestamp":1619436643000},"page":"e043786","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":24,"title":["Determinants of short birth intervals among married women: a cross-sectional study in Karachi, Pakistan"],"prefix":"10.1136","volume":"11","author":[{"given":"Sidrah","family":"Nausheen","sequence":"first","affiliation":[{"name":"Obstetrics & Genecology, Aga Khan University, Karachi, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Bhura","sequence":"additional","affiliation":[{"name":"Center of Excellence in Women & Child Health, Aga Khan University, Karachi, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3969-659X","authenticated-orcid":false,"given":"Kristy","family":"Hackett","sequence":"additional","affiliation":[{"name":"Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Imtiaz","family":"Hussain","sequence":"additional","affiliation":[{"name":"Pediatrics & Child Health, Aga Khan University, Karachi, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zainab","family":"Shaikh","sequence":"additional","affiliation":[{"name":"Center of Excellence & Child Health, Aga Khan University, Karachi, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arjumand","family":"Rizvi","sequence":"additional","affiliation":[{"name":"Pediatrics & Child Health, Aga Khan University, Karachi, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Uzair","family":"Ansari","sequence":"additional","affiliation":[{"name":"Pediatrics & Child Health, Aga Khan University, Karachi, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Canning","sequence":"additional","affiliation":[{"name":"Harvard T.H. 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